Air Quality Action Planning Consultation

Why are we doing this? : 

Merthyr Tydfil County Borough Council has monitored air pollution at a number of locations across the whole Borough for over seventeen years.

During this period only one pollutant, nitrogen dioxide, has been found to be present at levels in excess of the Government’s objective levels. These objective levels are set for the protection of the health of the public and for nitrogen dioxide there are two; one to protect from exposure to high levels for short periods and one to protect from exposure to low levels year on year. We have so far found no locations where the levels so high that people exposed for the shorter, one hour, period. However, we have found one location half-way up Twynyrodyn Road where the levels exceed the annual mean objective of 40 microgrammes per cubic metre.

When it was found, a study was carried out and action taken to deal with it. This improved the air quality there but subsequent increases in road traffic on the road caused the concentrations of nitrogen dioxide to rise again. Nitrogen dioxide is produced when fuel is burned and in most cases road vehicles are the main source.

The Council declared an Air Quality Management Area (AQMA) on 30th January 2017. This covered the area of exceedance and also the section of Twynyrodyn Road down to the roundabout outside Tesco as shown in the Twynyrodyn Air Quality Management Area map (see documents below).  

What do we want to know?: 

After declaring the AQMA the Council is allowed up to eighteen months to study the problem and produce an Action Plan designed to lower the pollution to below the objective levels.

The Council has studied a very large number of alternatives (the full study is available at the Civic Centre on request) and has found a small number capable of dealing with the problem.

Since the problem is caused by road traffic, and changing the types of vehicles using the road would have little effect, the aim has been to reduce the numbers of vehicles using the affected section of Twynyrodyn Road.

For some of the proposals considered, their likelihood of success depends on the destinations drivers are trying to reach and the routes they are taking to reach them. A further traffic study is being carried out at the moment to determine whether they could be successful or not and if so, they will expand the range of viable options. However, as they are more limited in effect and currently of questionable value they are not included in this consultation.

The options given here are all capable of protecting the health of the residents in Twynyrodyn Road.  They are arranged in order of the benefits and disadvantages they might cause to the residents, traders, drivers and other people affected by the measures.

Since our aim is firstly to protect the health of all members of the public we favour options which, as far as possible, do not increase traffic in other areas where people would be exposed. Since drivers are also exposed to high levels of air pollution in their vehicles their exposure is reduced by keeping journeys short and avoiding congestion.

Only one solution meets all of these aims and this is given first with the rest following. Your views on all of the options are welcomed and will be taken into account before the Action Plan is finalised and submitted to the Welsh Government.

Summary of Available Measures




Reversal of one-way traffic on both Pontmorlais High Street and Church Street.



Reversal of one-way traffic on Pontmorlais High Street and Church Street opened to two-way traffic*



Provision of a chicane on Twynyrodyn Road between Windsor Terrace and Queens Road



All west-bound traffic on Twynyrodyn Road diverted at Queens Road with no left turn onto Queens Road for east-bound traffic








*The Automatic Number Plate Recognition currently in progress will determine how effective this is likely to be.











Consultation start date16 March 2018
Consultation end date07 June 2018
Contact details:
Consultation run by: Merthyr Tydfil County Borough Council
MTCBC Consultation